Migration Guide
Welcome to SFML 3! The SFML Team has put a lot of effort into delivering a library that is both familiar to existing users while also making significant improvements. This document will walk you through how to upgrade your SFML 2 application to SFML 3.
One of the headline changes in SFML 3 is raising the C++ standard to C++17 thus bringing SFML into the world of modern C++! This change has enabled a vast number of internal improvements as well as new opportunities for improving the API that will be discussed in this document.
Compiler Requirements
Along with the upgrade from C++03 to C++17 you may need to upgrade your compiler. C++17 support has been widespread in all major compiler implementations for years prior to SFML 3's release so in all likelihood the compiler you're already using will work. In case you do need to upgrade, here are the minimum compiler versions.
Compiler | Version |
---|---|
MSVC | 16 (VS 2019) |
GCC | 9 |
Clang | 9 |
AppleClang | 12 |
CMake Targets
SFML 3 uses modern CMake convention for library targets which entails having a namespace in front of the target name.
These namespaces tell CMake "this is a target" whereas something like sfml-graphics
might be a target or might be a precompiled library on disk like libsfml-graphics.so
.
Fixing this ambiguity leads to more useful error messages when a given target can't be found due to, for example, forgetting a find_package
call.
The component names used when calling find_package
were also changed to capitalize the first letter.
v2 Target | v3 Target |
---|---|
sfml-system |
SFML::System |
sfml-window |
SFML::Window |
sfml-graphics |
SFML::Graphics |
sfml-network |
SFML::Network |
sfml-audio |
SFML::Audio |
sfml-main |
SFML::Main |
v2 Component | v3 Component |
---|---|
system |
System |
window |
Window |
graphics |
Graphics |
network |
Network |
audio |
Audio |
main |
Main |
v2:
find_package(SFML 2 REQUIRED COMPONENTS graphics audio network)
...
target_link_libraries(my_app PRIVATE sfml-graphics sfml-audio sfml-network)
v3:
find_package(SFML 3 REQUIRED COMPONENTS Graphics Audio Network)
...
target_link_libraries(my_app PRIVATE SFML::Graphics SFML::Audio SFML::Network)
sf::Vector2<T>
Parameters
A common pattern in SFML 2 was to use pairs of scalar parameters to represent concepts like sizes or positions.
Take sf::Transformable::setPosition(float, float)
for example.
The two parameters combine to represent a position in world space.
SFML 3 takes all of the APIs with pairs of parameters like (float, float)
or (unsigned int, unsigned int)
and converts them to their corresponding sf::Vector2<T>
type like sf::Vector2f
or sf::Vector2u
to make the interface more expressive and composable.
This transition is often as simple as wrapping the two adjacent parameters with braces to construct the vector.
v2:
sf::VideoMode videoMode(480, 640, 24);
sf::CircleShape circle(10);
circle.setPosition(10, 20);
sf::IntRect rect(250, 400, 50, 100);
v3:
sf::VideoMode videoMode({480, 640}, 24);
sf::CircleShape circle(10);
circle.setPosition({10, 20});
sf::IntRect rect({250, 400}, {50, 100});
Fixed Width Integers
SFML 2 contained various typedefs for fixed width integers.
Those are now replaced with the fixed width integers provided in the <cstdint>
header from the standard library.
v2 | v3 |
---|---|
sf::Int8 |
std::int8_t |
sf::Uint8 |
std::uint8_t |
sf::Int16 |
std::int16_t |
sf::Uint16 |
std::uint16_t |
sf::Int32 |
std::int32_t |
sf::Uint32 |
std::uint32_t |
sf::Int64 |
std::int64_t |
sf::Uint64 |
std::uint64_t |
sf::Event
SFML 3 uses std::variant
under the hood to implement a totally new, type-safe API for events.
There are two main ways to use this new API.
Check out the new EventHandling example program to see these methods in practice.
sf::Event::getIf<T>
The first option is based around sf::Event::getIf<T>
and sf::Event::is<T>
.
getIf<T>
works by providing a template parameter which must be an event subtype.
Event subtypes are types like sf::Event::Resized
or sf::Event::MouseMoved
.
If the template argument matches the active event subtype then a pointer to the data is returned.
If that template argument is not the active event subtype then nullptr
is returned.
sf::Event::is<T>
more simply returns true
if T
matches the active event subtype.
is<T>
is often used for subtypes like sf::Event::Closed
which contain no data.
Here's what that looks like:
while (window.isOpen())
{
while (const std::optional event = window.pollEvent())
{
if (event->is<sf::Event::Closed>())
{
window.close();
}
else if (const auto* keyPressed = event->getIf<sf::Event::KeyPressed>())
{
if (keyPressed->scancode == sf::Keyboard::Scancode::Escape)
window.close();
}
}
// Remainder of main loop
}
Note how the API for getting events has changed slightly.
sf::WindowBase::pollEvent
and sf::WindowBase::waitEvent
now return a std::optional<sf::Event>
.
These two functions might return an event but they might not.
C++ lets you deduce the template parameter which is why you can write const std::optional event
instead of const std::optional<sf::Event> event
.
const auto event
is another valid choice if you prefer a more terse expression.
sf::WindowBase::handleEvents
The second option for processing events is via the new sf::WindowBase::handleEvents
function.
This functions performs event visitation.
What this means is that you can provide callbacks which take different event subtypes as arguments.
Alternatively you may provide an object (or objects) with operator()
implementations which handle the event subtypes you want to process.
Notably you do not have to provide callbacks for all possible event subtypes.
Depending on the current active event subtype, the corresponding callback is called.
Here's what that looks like:
const auto onClose = [&window](const sf::Event::Closed&)
{
window.close();
};
const auto onKeyPressed = [&window](const sf::Event::KeyPressed& keyPressed)
{
if (keyPressed.scancode == sf::Keyboard::Scancode::Escape)
window.close();
};
while (window.isOpen())
{
window.handleEvents(onClose, onKeyPressed);
// Remainder of main loop
}
Window Styles and States
A new sf::State
enumeration was added for specifying the state of the window which means whether the window is floating or fullscreen.
Here's a before-and-after showing how this affects constructing a window.
v2:
v3:
Scoped Enumerations
SFML 3 converts all old style unscoped enumerations to scoped enumerations. This improves the type safety of the interface. This means that the name of the enumeration is now part of the namespace required to access values of that enumeration.
For example, take the enumeration sf::Keyboard::Key
.
sf::Keyboard::A
becomes sf::Keyboard::Key::A
.
The name of the enumeration now appears as a nested namespace when accessing one of the enumeration's values.
Here is a complete list of all enumerations which have undergone this change:
sf::BlendMode::Equation
sf::BlendMode::Factor
sf::Cursor::Type
sf::Ftp::Response::Status
sf::Ftp::TransferMode
sf::Http::Request::Method
sf::Http::Response::Status
sf::Joystick::Axis
sf::Keyboard::Key
sf::Keyboard::Scan
sf::Mouse::Button
sf::Mouse::Wheel
sf::PrimitiveType
sf::Sensor::Type
sf::Shader::Type
sf::Socket::Status
sf::Socket::Type
sf::SoundSource::Status
sf::VertexBuffer::Usage
sf::Rect<T>
sf::Rect<T>
has been refactored from the four scalar values top
, left
, width
, and height
into two sf::Vector2<T>
s named position
and size
.
This means that sf::Rect<T>::getPosition()
and sf::Rect<T>::getSize()
have been removed in favor of directly accessing the position
and size
data members.
The 4-parameter constructor was also removed in favor of the constructor which takes two sf::Vector2<T>
s.
v2:
sf::FloatRect rect(10, 20, 30, 40);
sf::Vector2f position = rect.getPosition();
sf::Vector2f size = rect.getSize();
v3:
sf::FloatRect rect({10, 20}, {30, 40});
sf::Vector2f position = rect.position;
sf::Vectro2f size = rect.size;
The two overloads of sf::Rect<T>::intersects
have been replaced with one unified function called sf::Rect<T>::findIntersection
which returns a std::optional<Rect<T>>
.
This optional contains the overlapping area if the rectangles overlap.
Otherwise the optional is empty.
sf::IntRect rect1({0, 0}, {200, 200});
sf::IntRect rect2({100, 100}, {200, 200});
std::optional<sf::IntRect> intersection = rect1.findIntersection(rect2);
// position={100, 100} size={100, 100}
sf::Angle
All angles are now represented with a strong type named sf::Angle
.
This type provides two functions for creating angles called sf::degrees(float)
and sf::radians(float)
which construct an angle from either some value of degrees or radians.
Operators (+
, -
, etc.) are provided to perform mathematical operations with angles.
If you need access to the raw angle as a float
then you can use either sf::Angle::asDegrees()
or sf::Angle::asRadians()
.
v2:
sf::RectangleShape shape(sf::Vector2f(50, 50));
shape.setRotation(90);
std::cout << "Rotation: " << shape.getRotation() << '\n';
v3:
sf::RectangleShape shape({50, 50});
shape.setRotation(sf::degrees(90));
std::cout << "Rotation: " << shape.getRotation().asDegrees() << '\n';
Renamed Functions
A number of functions have new names but otherwise have not changed their semantics.
v2 | v3 |
---|---|
sf::Font::loadFromFile |
sf::Font::openFromFile |
sf::Socket::getHandle |
sf::Socket::getNativeHandle |
sf::WindowBase::getSystemHandle |
sf::WindowBase::getNativeHandle |
sf::Texture::create |
sf::Texture::resize |
sf::RenderTexture::create |
sf::RenderTexture::resize |
sf::Image::create |
sf::Image::resize |
sf::Sound::getLoop |
sf::Sound::isLooping |
sf::Sound::setLoop |
sf::Sound::setLooping |
sf::SoundStream::getLoop |
sf::SoundStream::isLooping |
sf::SoundStream::setLoop |
sf::SoundStream::setLooping |
Removal of Default Constructors
The default constructors sf::Sound::Sound()
, sf::Text::Text()
, and sf::Sprite::Sprite()
were removed.
They can be replaced by the corresponding constructors which accept a resource type.
v2 | v3 |
---|---|
sf::Sound::Sound() |
sf::Sound::Sound(const sf::SoundBuffer&) |
sf::Text::Text() |
sf::Text::Text(const sf::Font&) |
sf::Sprite::Sprite() |
sf::Sprite::Sprite(const sf::Texture&) |
Now that these classes are guaranteed to be holding a reference to their corresponding resource type, the functions used to access to those resources can return a reference instead of a pointer.
These functions are sf::Sound::getBuffer()
, sf::Text::getFont()
, and sf::Sprite::getTexture()
.
v2:
v3:
std::optional
Usage
SFML 3 makes liberal use of std::optional
to express when a given function may not return a value.
Some of these usages have already been mentioned like sf::WindowBase::pollEvent
.
Here are some more places where SFML 3 makes use of std::optional
.
sf::IpAddress
usesstd::optional
to express how resolving an address from a string may not yield a usable IP address.sf::Image::saveToMemory
returns astd::optional
because thesf::Image
may be empty or the underlying implementation may fail.sf::SoundFileReader::open
returns astd::optional
because the stream being opened may not be valid.sf::Music::onLoop
andsf::SoundStream::onLoop
returns astd::optional
because if the objects are not in a looping state then there is nothing to return.sf::InputStream
usesstd::optional
in various places. Instead of returning-1
to signal an error,std::nullopt
can be returned.
LearnCpp.com is a great place to learn more about using std::optional
.
Read more about that here.
New Constructors for Loading Resources
The following classes gained constructors that allow for loading/opening resources in a single expression.
Upon failure they throw an sf::Exception
.
sf::InputSoundFile
sf::OutputSoundFile
sf::Music
sf::SoundBuffer
sf::Font
sf::Image
sf::RenderTexture
sf::Shader
sf::Texture
sf::FileInputStream
sf::Cursor
SFML 3 still supports the SFML 2 style of error handling in addition to these new constructors.
v2:
v3:
sf::SoundBuffer soundBuffer;
if (!soundBuffer.loadFromFile("sound.wav"))
{
// Handle error
}
// OR
const sf::SoundBuffer soundBuffer("sound.wav");
sf::Vector2<T>
and sf::Vector3<T>
Utility Functions
sf::Vector2<T>
and sf::Vector3<T>
gained a number of new functions for performing common mathematic operations on vectors.
sf::Vector2<T> Function |
Description |
---|---|
Vector2(T, sf::Angle) |
Construct from polar coordinates |
length() |
Get length |
lengthSquared() |
Get length squared |
normalized() |
Get vector normalized to unit circle |
angleTo(sf::Vector2) |
Get angle to another vector |
angle() |
Get angle from X axis |
rotatedBy(sf::Angle) |
Get vector rotated by a given angle |
projectedOnto(sf::Vector2) |
Get vector projected onto another vector |
perpendicular() |
Get perpendicular vector |
dot(sf::Vector2) |
Get dot product |
cross(sf::Vector2) |
Get Z component of cross product |
componentWiseMul(sf::Vector2) |
Get component-wise multiple |
componentWiseDiv(sf::Vector2) |
Get component-wise divisor |
sf::Vector3<T> Function |
Description |
---|---|
length() |
Get length |
lengthSquared() |
Get length squared |
normalized() |
Get vector normalized to unit circle |
dot(sf::Vector3) |
Get dot product |
cross(sf::Vector3) |
Get cross product |
componentWiseMul(sf::Vector3) |
Get component-wise multiple |
componentWiseDiv(sf::Vector3) |
Get component-wise divisor |
Threading Primitives
sf::Lock
, sf::Mutex
, sf::Thread
, sf::ThreadLocal
, and sf::ThreadLocalPtr
were removed and replaced with their equivalents from the standard library.
The standard library provides multiple options for threads, locks, and mutexes among other threading primitives.
v2 | v3 |
---|---|
sf::Lock |
std::lock_guard or std::unique_lock |
sf::Mutex |
std::mutex or std::recursive_mutex |
sf::Thread |
std::thread or std::jthread (requires C++20) |
sf::ThreadLocal |
thread_local |
sf::ThreadLocalPtr |
thread_local |
Sound Samples and Channel Map
SFML 3 introduces the concept of a Channel Map which defines the mapping of the position in sample frame to the sound channel. For example, if you have a sound frame with six different samples for a 5.1 sound system, the Channel Map defines how each of those samples map to which speaker channel.
SFML 2 always assumed the order as specified by OpenAL.
auto samples = std::vector<std::int16_t>();
// ...
auto channelMap = std::vector<sf::SoundChannel>{
sf::SoundChannel::FrontLeft,
sf::SoundChannel::FrontCenter,
sf::SoundChannel::FrontRight,
sf::SoundChannel::BackRight,
sf::SoundChannel::BackLeft,
sf::SoundChannel::LowFrequencyEffects
};
auto soundBuffer = sf::SoundBuffer(samples.data(), samples.size(), channelMap.size(), 44100, channelMap);
auto sound = sf::Sound(soundBuffer);
This a breaking change for the following APIs:
bool sf::SoundBuffer::loadFromSamples(...)
bool sf::SoundBuffer::update(...)
void sf::SoundStream::initialize(...)
bool sf::OutputSoundFile::openFromFile(...)
bool sf::SoundFileWriter::open(...)
Deprecated APIs
SFML 3 removes all of the deprecated APIs in SFML 2.
Deprecated API | Replacement |
---|---|
sf::Event::MouseWheelEvent |
sf::Event::MouseWheelScrolled |
sf::RenderWindow::capture |
See 1 |
sf::RenderTexture::create |
sf::RenderTexture::resize |
sf::Shader::setParameter |
sf::Shader::setUniform |
sf::Text::setColor |
sf::Text::setFillColor |
sf::Text::getColor |
sf::Text::getFillColor |
sf::PrimitiveType::LinesStrip |
sf::PrimitiveType::LineStrip |
sf::PrimitiveType::TrianglesStrip |
sf::PrimitiveType::TriangleStrip |
sf::PrimitiveType::TrianglesFan |
sf::PrimitiveType::TriangleFan |
sf::PrimitiveType::Quads |
See 2 |
sf::RenderWindow::capture
can be recreated by using ansf::Texture
and itssf::Texture::update(const Window&)
function to copy its contents into ansf::Image
instead.sf::PrimitiveType::Quads
can be replaced by another primitive type. This is not a drop-in replacement but rather will require refactoring your code to work with a new geometry. One viable option is to usesf::PrimitiveType::Triangles
where two adjacent triangles join to form what was previously one quad.
Anti-Aliasing Renamed
SFML 3 capitalizes the A
of aliasing
for all the APIs.
sf::RenderTexture::getMaximumAntialiasingLevel()
becomessf::RenderTexture::getMaximumAntiAliasingLevel()
sf::ContextSettings::antialiasingLevel
becomessf::ContextSettings::antiAliasingLevel
Other Minor Changes
SFML 3 includes various smaller changes that ought to be mentioned.
- Changed the parameter order of the
sf::Text
constructor, so that the provided font is always the first parameter - Reverted to default value of CMake's
BUILD_SHARED_LIBS
which means SFML now builds static libraries by default - Changed
sf::String
interface to usestd::u16string
andstd::u32string
- Removed
sf::ContextSettings
constructor in favor of aggregate initialization - Removed
sf::View::reset
in favor of assigning from a newsf::View
object - Added new
sf::CoordinateType
enumeration tosf::RenderStates::RenderStates
- Removed
sf::Vertex
constructors in favor of aggregate initialization - Renamed
sf::Mouse::Button::XButton1
andsf::Mouse::Button::XButton2
enumerators tosf::Mouse::Button::Extra1
andsf::Mouse::Button::Extra2
- Removed NonCopyable.hpp header in favor of using built-in language features for disabling copy operators
- Converted the following classes to namespaces:
sf::Clipboard
,sf::Keyboard
,sf::Joystick
,sf::Listener
,sf::Mouse
,sf::Sensor
,sf::Touch
,sf::Vulkan
- Removed
sf::SoundStream::setProcessingInterval
as miniaudio matches the internal processing rate to the underlying backend